Fire-extinguishing syringe.



. H. MERRITT. Y FIRE BXTINGUISHING SYRINGE.

APPLICATION FILED APR.12, 1912.

Patented July 22, 1913.

UNITED STATES FiaTENT OFFICE.

HIRAM MERRITT, OF NEWBURGH, NEW YORK.

FIRE-EXTINGUISHING SYRINGE.

T0 all whom it may concern Be it known that I, HIRAM MERRITT, a

citizen` of the United States, residing at Newburgh, New York, haveinvented certain new and useful Improvements in Fire-EX- tinguishingSyringes, of which the following is a clear, full, and exactdescription.

This invention relates to a fire extinguishing syringe of the reservoirtype, containing a reserve supply of fire extinguishing fluid which maybe ejectedby a series of pumping strokes.

One of the objects of my invention is to improve the generalconstruction of such devices whereby the operation is ni'ade more simpleand eiiicient, and whereby the apparatus when not in use will be closedagainst leakage. The tire extinguishing fluid com- -monly employed indevices of this kind such as carbon tetrachlorid has an Obnoxious smell,and therefore any drip or leakage from the syringe when not in use isobjectionable.

The invention is particularly ap licable to the type` of fireextinguishers w ich comprises a reservoir and a barrel or pump cylindexrin communication with the reservoir.

One of the objects of my invention is to reduce the force necessary todrive the piston on the forward stroke and to accelerate the fillingmovement of the liquid into the pump chamber on the return stroke.

My invention therefore comprises the general combination of parts anddetails of construction hereinafter specified, and it is to beunderstood that all variations within the spirit of my invention arebroadly embodied in the appended claims.

ln the preferred embodiment shown in the drawings, Figure 1 is anelevation of the device with the portion of the nozzle cut away; Fig. 2is a vertical section of the saine complete; Fig. 3 is a cross sectionthrough the line 3 3 of Fig. 2; Fig. 4 is a cross section through line 44 Fig.`2; and Fig. 5 is an enlarged detail of the charging cap and inletvalve.

Referring more particularly to the drawings, the syringe as a wholecomprises an outer cylindrical shell l having within the same a tubularpartition 2 spaced from the inner wall of the shell so as to form twoseparate inner compartments. the central cnmjivartment or pumpingchamber 4 and the annular compartment 3 outside thereof.l all as shownclearly in Fig. 2. A per- Specification of Letters Patent.

Patented July 22, 1913.

Application led April 12, 1912. Serial No. 690,258.

forated partition 2a at the upper end of compartment 3 provides freecommunication between the reservoir to this end of the pumping chamber4, as shown. At the other end of compartment 3 are preferably locatedone or more inlet valves 16 providing communication between thereservoir and pumping chamber at this end. As shown, eachvalve 16preferably consists of a spring pressed .disk 17 normally held closed byspring 18 and adapted to be opened inwardly by pressure from the outsideand closed'by pressure from the inside.

The ejecting end of the syringe is provided with the usual closure orhead 9 preferably screw threaded on the shell 1 and having therethroughthe outlet passage 21. A tapered nozzle 18 is also preferably screwthreaded on the end of closure 9 having therethrough a continuation ofoutlet 2ll and also provided with a spring pressed valve plug 19normally closing outlet passage 21 under pressure of spring 2O as shown.It is obvious that this valve 19.will give way to an outward pressurefrom within the syringe so thatl the contained fluid may be easilyejected. The syringe is charged through opening 23 at the upper end of/shell 1 which is covered by the charging cap 13 preferably screwthreaded on the closure head 8 as shown. The cap 13 is also providedwith a spring pressed inlet valve 14 normally held closed by spring 15.whereby air is a-:nniited to the, interi-v r of said shell to maintainnormal atmospheric pressure within the cylinder during the pumpingaction.

Working within the pumping chamber 4 is an ordinary form of piston 5having rod 6 extending through closure head 8 to a' handle 7. Thesliding joint of rod 6 is closed against leakage by the usual packingarrangement 22. and said rod 6 is also preferably provided with abayonet collar 10 fixed thereto as shown in Fig. 2, and adapted tocoperate with a pin 12 upon closure 8 as shown in Fig. 1. The piston 5is also .preferably provided with a tapered projection 5a at its lowerend, adapted to seat within a tapered socket 9 of head The piston j rod6 is adapted to be forced downwardly and firmly locked in position bymeans of its bayonet joint 1l, 12 to firmly seat the said taperedprojection 5 within socket Wand thus seal the shell against any possibleleakage at either end.

Ytents of the pumping chamber 3 through y adapted to be reeiprocatedrepeatedly with-- The operation of the device is already apparentfromthedescril'ition heretofore given, but may be briefly recounted asfollows: The entire space within shell 1 may be first charged with fireextinguishing liquid through inlet L3. The upward stroke of piston 5both sucks liquid through valve 16 from the reservoir 3 into pumpingchamber 4, and also forces the liquid behind piston 5 around throughopenings 2b of partition 2 into reservoir .3, so as to mechanicallyforce the liquid in fr'ont of piston k downward stroke of the piston ofcourse ejeets the conoutlet 21, and this operation may be repeated untilthe entire contents of both pumping chamber and reservoir are exhausted.lt will be observed that the present construction not only provides fora pumpinv action by suction upon the withdrawal of piston 5, but also byproviding free communication between the central pumping chamber 4 andreservoir 3, a force pumping act-ion takes place behind the piston 5 soas to more effeetually bring the liquid in front of the piston. Thisforce pumping action of course takes place behind piston 'i whether airor liquid is within said central pumping chamber.

What I claim as new is1-- 1. A fire extinguishing hand-syringecomprising in combination la reservoir, a pumping chamber adjacentthereto, a piston adapted to be reciproeated repeatedly within saidpumping chamber to empty the same, said pumping chamber communicatingwith said reservoir at the forward and rear ends of said pumpingchamber, and an air inlet valve for admitting air on the forward strokeof said piston and preventing an outward How of air on the back strokeof said piston whereby the air in the rear of said reservoir iscompressed, and the flow of liquid accelerated from said reservoir intothe forward end of said pumping chamber` and means for preventing areturn {iow of the liquid from the forward end of said pumping chamberto said reservoir on the forward stroke of said piston.

2. A fire extinguishing handsyringe comprising in combination areservoir, a pu1nping chamber adjacentV thereto, a piston in saidpumping chamber to empty the sami'. .said pumping chan'ibereommunicating with said reservoir at the forward and rear endsv of saidpumping chamber, and an air inlet valve for admitting air on the forwardi Stroke of said piston and pI'c\'ciitiiig au dutward flow of air on theback stroke of said piston whereby the air -m the rear of said lreservoir is compressed, and the [low of liquid accelerated from saidreservoir into the forward yend of said pumping chamber, and valvesbetween said reservoir andthe forward end of said pumpingl chamber openNing from said reservoir to said pump chaluber and preventing a returnflow of the liquid from said pump chamber to said reservoir on theforward Stroke of said piston.

3. A fire extinguishing hand-syringe comprisiA in 'combination an outershell normally closed to the atmosphere and having within the same areservoir, a pumping chamber a:-'iacent to said reservoir, a pistonadapted to be reciprocated repeatedly within said pumping chauiber toempty the fame said pumping chamber eenununicatiugr with the reservoirat the forward and rear ends of said pumping chamber, an air inlrt valvefor admitting air rn the forward stroke ot' said pis-ten and preventingan outward tion of air on the back stroke of said piston wl'lereby theair in the rear of said reservoir is compressed and the flow of liquidaccelerated frcm said reservoir into the forward end ofr said pumpingchamber, means for preventing a return flow of the liquid from theforward end of said pumping chamber to said reservoir on the forwardstroke of said piston, said syringe having a discharge outlet, and meansin said discharge outlet for preventing an out *ard flow of the liquidcn the backward stroke of said piston.

4. A fire extinguishing hand-syringe comprising in combination an outershell normally closed to the atmosphere and having within the same. areservoir, `a pumping chamber adjacentJ to said reservoir, a pistcnadapted to be reciprocatrd repeatedly within said pumping chamber toempty the same, said pumping chamber communicating with the reservoir atthe forward and rear endsof said pumping chamber, an air inlet Avalvefor admitting air on the forward stroke of said piston and preventing anoutward tioiv of air on the back stroke of said piston whereby the airEn the rear of said reservoir is compressed and the 'iicw of liquidaccelerated from said reservoir into the forward end of said pumpingehauiber, and a valve in connection with said discharge outlet toprevent' dripping cf the, liquid through said discharge outiet on thebackward strelte of said piston.

Signed at Newburgh, N. Y., this 10th dav ai' April wie.

Hman Mriuiu'rr.

litnessesr Erm ldeCi:.\cmiN, FRANK J. lliiwiUNs.

